Home Page and Related Options Missing

I use WordPress software for my blog, and have been doing so for about six months. Today, I noticed that my home page does not exist (I just get "page not found" error) and that the options on the "reading" page related to the home page are no longer there. (I.E. the options for static page or feed for the home page). The home page existed in the day before last although I have not changed any settings in a while, so I don't know when the settings disappeared.

The only changes I have made in the last two days were updating Jetpack and one other plug-in, although I forget what. There was a few other updates that I did, and a new post, right before last checking the homepage. Could a plug-in have changed the basic WordPress menu options? Also, I don't really remember what I updated, but if there was a WordPress update, I installed that.

Edit: All pages and posts, including one i edited no more than an hour ago, have disappeared. I have no changed anything since i edited that page. All I did was remove one line of text that was still there from my draft. I have no idea how this could have happened.